//
// execution/blocking_adaptation.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//

#ifndef ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP
#define ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include "asio/detail/config.hpp"
#include "asio/detail/event.hpp"
#include "asio/detail/mutex.hpp"
#include "asio/detail/type_traits.hpp"
#include "asio/execution/execute.hpp"
#include "asio/execution/executor.hpp"
#include "asio/execution/scheduler.hpp"
#include "asio/execution/sender.hpp"
#include "asio/is_applicable_property.hpp"
#include "asio/prefer.hpp"
#include "asio/query.hpp"
#include "asio/require.hpp"
#include "asio/traits/prefer_member.hpp"
#include "asio/traits/query_free.hpp"
#include "asio/traits/query_member.hpp"
#include "asio/traits/query_static_constexpr_member.hpp"
#include "asio/traits/require_member.hpp"
#include "asio/traits/static_query.hpp"
#include "asio/traits/static_require.hpp"

#include "asio/detail/push_options.hpp"

namespace asio {

#if defined(GENERATING_DOCUMENTATION)

    namespace execution {

    /// A property to describe whether automatic adaptation of an executor is
    /// allowed in order to apply the blocking_adaptation_t::allowed_t property.
    struct blocking_adaptation_t
    {
      /// The blocking_adaptation_t property applies to executors, senders, and
      /// schedulers.
      template <typename T>
      static constexpr bool is_applicable_property_v =
        is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;

      /// The top-level blocking_adaptation_t property cannot be required.
      static constexpr bool is_requirable = false;

      /// The top-level blocking_adaptation_t property cannot be preferred.
      static constexpr bool is_preferable = false;

      /// The type returned by queries against an @c any_executor.
      typedef blocking_adaptation_t polymorphic_query_result_type;

      /// A sub-property that indicates that automatic adaptation is not allowed.
      struct disallowed_t
      {
        /// The blocking_adaptation_t::disallowed_t property applies to executors,
        /// senders, and schedulers.
        template <typename T>
        static constexpr bool is_applicable_property_v =
          is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;

        /// The blocking_adaptation_t::disallowed_t property can be required.
        static constexpr bool is_requirable = true;

        /// The blocking_adaptation_t::disallowed_t property can be preferred.
        static constexpr bool is_preferable = true;

        /// The type returned by queries against an @c any_executor.
        typedef blocking_adaptation_t polymorphic_query_result_type;

        /// Default constructor.
        constexpr disallowed_t();

        /// Get the value associated with a property object.
        /**
         * @returns disallowed_t();
         */
        static constexpr blocking_adaptation_t value();
      };

      /// A sub-property that indicates that automatic adaptation is allowed.
      struct allowed_t
      {
        /// The blocking_adaptation_t::allowed_t property applies to executors,
        /// senders, and schedulers.
        template <typename T>
        static constexpr bool is_applicable_property_v =
          is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;

        /// The blocking_adaptation_t::allowed_t property can be required.
        static constexpr bool is_requirable = true;

        /// The blocking_adaptation_t::allowed_t property can be preferred.
        static constexpr bool is_preferable = false;

        /// The type returned by queries against an @c any_executor.
        typedef blocking_adaptation_t polymorphic_query_result_type;

        /// Default constructor.
        constexpr allowed_t();

        /// Get the value associated with a property object.
        /**
         * @returns allowed_t();
         */
        static constexpr blocking_adaptation_t value();
      };

      /// A special value used for accessing the blocking_adaptation_t::disallowed_t
      /// property.
      static constexpr disallowed_t disallowed;

      /// A special value used for accessing the blocking_adaptation_t::allowed_t
      /// property.
      static constexpr allowed_t allowed;

      /// Default constructor.
      constexpr blocking_adaptation_t();

      /// Construct from a sub-property value.
      constexpr blocking_adaptation_t(disallowed_t);

      /// Construct from a sub-property value.
      constexpr blocking_adaptation_t(allowed_t);

      /// Compare property values for equality.
      friend constexpr bool operator==(
          const blocking_adaptation_t& a, const blocking_adaptation_t& b) noexcept;

      /// Compare property values for inequality.
      friend constexpr bool operator!=(
          const blocking_adaptation_t& a, const blocking_adaptation_t& b) noexcept;
    };

    /// A special value used for accessing the blocking_adaptation_t property.
    constexpr blocking_adaptation_t blocking_adaptation;

    } // namespace execution

#else // defined(GENERATING_DOCUMENTATION)

    namespace execution {
        namespace detail {
            namespace blocking_adaptation {

                template<int I>
                struct disallowed_t;
                template<int I>
                struct allowed_t;

            } // namespace blocking_adaptation

            template<int I = 0>
            struct blocking_adaptation_t {
#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
                template <typename T>
                ASIO_STATIC_CONSTEXPR(bool,
                  is_applicable_property_v = (
                    is_executor<T>::value
                      || conditional<
                          is_executor<T>::value,
                          false_type,
                          is_sender<T>
                        >::type::value
                      || conditional<
                          is_executor<T>::value,
                          false_type,
                          is_scheduler<T>
                        >::type::value));
#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)

                ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);

                ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);

                typedef blocking_adaptation_t polymorphic_query_result_type;

                typedef detail::blocking_adaptation::disallowed_t<I> disallowed_t;
                typedef detail::blocking_adaptation::allowed_t<I> allowed_t;

                ASIO_CONSTEXPR blocking_adaptation_t()
                        : value_(-1) {
                }

                ASIO_CONSTEXPR blocking_adaptation_t(disallowed_t)
                        : value_(0) {
                }

                ASIO_CONSTEXPR blocking_adaptation_t(allowed_t)
                        : value_(1) {
                }

                template<typename T>
                struct proxy {
#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
                    struct type
                    {
                      template <typename P>
                      auto query(ASIO_MOVE_ARG(P) p) const
                        noexcept(
                          noexcept(
                            declval<typename conditional<true, T, P>::type>().query(
                              ASIO_MOVE_CAST(P)(p))
                          )
                        )
                        -> decltype(
                          declval<typename conditional<true, T, P>::type>().query(
                            ASIO_MOVE_CAST(P)(p))
                        );
                    };
#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
                    typedef T type;
#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
                };

                template<typename T>
                struct static_proxy {
#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
                    struct type
                    {
                      template <typename P>
                      static constexpr auto query(ASIO_MOVE_ARG(P) p)
                        noexcept(
                          noexcept(
                            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
                          )
                        )
                        -> decltype(
                          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
                        )
                      {
                        return T::query(ASIO_MOVE_CAST(P)(p));
                      }
                    };
#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
                    typedef T type;
#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
                };

                template<typename T>
                struct query_member :
                        traits::query_member<typename proxy<T>::type, blocking_adaptation_t> {
                };

                template<typename T>
                struct query_static_constexpr_member :
                        traits::query_static_constexpr_member<
                                typename static_proxy<T>::type, blocking_adaptation_t> {
                };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
                template <typename T>
                static ASIO_CONSTEXPR
                typename query_static_constexpr_member<T>::result_type
                static_query()
                  ASIO_NOEXCEPT_IF((
                    query_static_constexpr_member<T>::is_noexcept))
                {
                  return query_static_constexpr_member<T>::value();
                }

                template <typename T>
                static ASIO_CONSTEXPR
                typename traits::static_query<T, disallowed_t>::result_type
                static_query(
                    typename enable_if<
                      !query_static_constexpr_member<T>::is_valid
                    >::type* = 0,
                    typename enable_if<
                      !query_member<T>::is_valid
                    >::type* = 0,
                    typename enable_if<
                      traits::static_query<T, disallowed_t>::is_valid
                    >::type* = 0) ASIO_NOEXCEPT
                {
                  return traits::static_query<T, disallowed_t>::value();
                }

                template <typename T>
                static ASIO_CONSTEXPR
                typename traits::static_query<T, allowed_t>::result_type
                static_query(
                    typename enable_if<
                      !query_static_constexpr_member<T>::is_valid
                    >::type* = 0,
                    typename enable_if<
                      !query_member<T>::is_valid
                    >::type* = 0,
                    typename enable_if<
                      !traits::static_query<T, disallowed_t>::is_valid
                    >::type* = 0,
                    typename enable_if<
                      traits::static_query<T, allowed_t>::is_valid
                    >::type* = 0) ASIO_NOEXCEPT
                {
                  return traits::static_query<T, allowed_t>::value();
                }

                template <typename E,
                    typename T = decltype(blocking_adaptation_t::static_query<E>())>
                static ASIO_CONSTEXPR const T static_query_v
                  = blocking_adaptation_t::static_query<E>();
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
                //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

                friend ASIO_CONSTEXPR bool operator==(
                        const blocking_adaptation_t &a, const blocking_adaptation_t &b) {
                    return a.value_ == b.value_;
                }

                friend ASIO_CONSTEXPR bool operator!=(
                        const blocking_adaptation_t &a, const blocking_adaptation_t &b) {
                    return a.value_ != b.value_;
                }

                struct convertible_from_blocking_adaptation_t {
                    ASIO_CONSTEXPR convertible_from_blocking_adaptation_t(
                            blocking_adaptation_t) {
                    }
                };

                template<typename Executor>
                friend ASIO_CONSTEXPR blocking_adaptation_t

                query(
                        const Executor &ex, convertible_from_blocking_adaptation_t,
                        typename enable_if<
                                can_query<const Executor &, disallowed_t>::value
                        >::type * = 0)

#if !defined(__clang__) // Clang crashes if noexcept is used here.
#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
                ASIO_NOEXCEPT_IF((
                  is_nothrow_query<const Executor&,
                    blocking_adaptation_t<>::disallowed_t>::value))
#else // defined(ASIO_MSVC)
                ASIO_NOEXCEPT_IF((
                        is_nothrow_query<const Executor &, disallowed_t>::value))
#endif // defined(ASIO_MSVC)
#endif // !defined(__clang__)
                        {
                                return asio::query(ex, disallowed_t());
                        }

                template<typename Executor>
                friend ASIO_CONSTEXPR blocking_adaptation_t

                query(
                        const Executor &ex, convertible_from_blocking_adaptation_t,
                        typename enable_if<
                                !can_query<const Executor &, disallowed_t>::value
                        >::type * = 0,
                        typename enable_if<
                                can_query<const Executor &, allowed_t>::value
                        >::type * = 0)

#if !defined(__clang__) // Clang crashes if noexcept is used here.
#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
                ASIO_NOEXCEPT_IF((
                  is_nothrow_query<const Executor&,
                    blocking_adaptation_t<>::allowed_t>::value))
#else // defined(ASIO_MSVC)
                ASIO_NOEXCEPT_IF((
                        is_nothrow_query<const Executor &, allowed_t>::value))
#endif // defined(ASIO_MSVC)
#endif // !defined(__clang__)
                        {
                                return asio::query(ex, allowed_t());
                        }

                ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(disallowed_t, disallowed
                );
                ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(allowed_t, allowed
                );

#if !defined(ASIO_HAS_CONSTEXPR)
                static const blocking_adaptation_t instance;
#endif // !defined(ASIO_HAS_CONSTEXPR)

            private:
                int value_;
            };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
            template <int I> template <typename E, typename T>
            const T blocking_adaptation_t<I>::static_query_v;
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
            //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

#if !defined(ASIO_HAS_CONSTEXPR)
            template<int I>
            const blocking_adaptation_t<I> blocking_adaptation_t<I>::instance;
#endif

            template<int I>
            const typename blocking_adaptation_t<I>::disallowed_t
                    blocking_adaptation_t<I>::disallowed;

            template<int I>
            const typename blocking_adaptation_t<I>::allowed_t
                    blocking_adaptation_t<I>::allowed;

            namespace blocking_adaptation {

                template<int I = 0>
                struct disallowed_t {
#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
                    template <typename T>
                    ASIO_STATIC_CONSTEXPR(bool,
                      is_applicable_property_v = (
                        is_executor<T>::value
                          || conditional<
                              is_executor<T>::value,
                              false_type,
                              is_sender<T>
                            >::type::value
                          || conditional<
                              is_executor<T>::value,
                              false_type,
                              is_scheduler<T>
                            >::type::value));
#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)

                    ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);

                    ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);

                    typedef blocking_adaptation_t<I> polymorphic_query_result_type;

                    ASIO_CONSTEXPR disallowed_t() {
                    }

                    template<typename T>
                    struct query_member :
                            traits::query_member<
                                    typename blocking_adaptation_t<I>::template proxy<T>::type,
                                    disallowed_t> {
                    };

                    template<typename T>
                    struct query_static_constexpr_member :
                            traits::query_static_constexpr_member<
                                    typename blocking_adaptation_t<I>::template static_proxy<T>::type,
                                    disallowed_t> {
                    };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
                    template <typename T>
                    static ASIO_CONSTEXPR
                    typename query_static_constexpr_member<T>::result_type
                    static_query()
                      ASIO_NOEXCEPT_IF((
                        query_static_constexpr_member<T>::is_noexcept))
                    {
                      return query_static_constexpr_member<T>::value();
                    }

                    template <typename T>
                    static ASIO_CONSTEXPR disallowed_t static_query(
                        typename enable_if<
                          !query_static_constexpr_member<T>::is_valid
                        >::type* = 0,
                        typename enable_if<
                          !query_member<T>::is_valid
                        >::type* = 0,
                        typename enable_if<
                          !traits::query_free<T, disallowed_t>::is_valid
                        >::type* = 0,
                        typename enable_if<
                          !can_query<T, allowed_t<I> >::value
                        >::type* = 0) ASIO_NOEXCEPT
                    {
                      return disallowed_t();
                    }

                    template <typename E, typename T = decltype(disallowed_t::static_query<E>())>
                    static ASIO_CONSTEXPR const T static_query_v
                      = disallowed_t::static_query<E>();
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
                    //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

                    static ASIO_CONSTEXPR blocking_adaptation_t<I>

                    value() {
                        return disallowed_t();
                    }

                    friend ASIO_CONSTEXPR bool operator==(
                            const disallowed_t &, const disallowed_t &) {
                        return true;
                    }

                    friend ASIO_CONSTEXPR bool operator!=(
                            const disallowed_t &, const disallowed_t &) {
                        return false;
                    }
                };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
                template <int I> template <typename E, typename T>
                const T disallowed_t<I>::static_query_v;
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
                //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

                template<typename Executor>
                class adapter {
                public:
                    adapter(int, const Executor &e)

                    ASIO_NOEXCEPT
                            : executor_(e)
                            {
                            }

                    adapter(const adapter &other)

                    ASIO_NOEXCEPT
                            : executor_(other.executor_)
                            {
                            }

#if defined(ASIO_HAS_MOVE)
                    adapter(adapter&& other) ASIO_NOEXCEPT
                      : executor_(ASIO_MOVE_CAST(Executor)(other.executor_))
                    {
                    }
#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)

                    template<int I>
                    static ASIO_CONSTEXPR allowed_t<I>
                    query(
                            blocking_adaptation_t<I>)
                    ASIO_NOEXCEPT
                    {
                        return allowed_t<I>();
                    }

                    template<int I>
                    static ASIO_CONSTEXPR allowed_t<I>
                    query(
                            allowed_t<I>)
                    ASIO_NOEXCEPT
                    {
                        return allowed_t<I>();
                    }

                    template<int I>
                    static ASIO_CONSTEXPR allowed_t<I>
                    query(
                            disallowed_t<I>)
                    ASIO_NOEXCEPT
                    {
                        return allowed_t<I>();
                    }

                    template<typename Property>
                    typename enable_if<
                            can_query<const Executor &, Property>::value,
                            typename query_result<const Executor &, Property>::type
                    >::type query(const Property &p) const

                    ASIO_NOEXCEPT_IF((
                            is_nothrow_query<const Executor &, Property>::value))
                            {
                                    return asio::query(executor_, p);
                            }

                    template<int I>
                    Executor require(disallowed_t <I>) const

                    ASIO_NOEXCEPT
                    {
                        return executor_;
                    }

                    template<typename Property>
                    typename enable_if<
                            can_require<const Executor &, Property>::value,
                            adapter<typename decay<
                                    typename require_result<const Executor &, Property>::type
                            >::type>
                    >::type require(const Property &p) const

                    ASIO_NOEXCEPT_IF((
                            is_nothrow_require<const Executor &, Property>::value))
                            {
                                    return adapter<typename decay<
                                    typename require_result<const Executor&, Property>::type
                                    >::type>(0, asio::require(executor_, p));
                            }

                    template<typename Property>
                    typename enable_if<
                            can_prefer<const Executor &, Property>::value,
                            adapter<typename decay<
                                    typename prefer_result<const Executor &, Property>::type
                            >::type>
                    >::type prefer(const Property &p) const

                    ASIO_NOEXCEPT_IF((
                            is_nothrow_prefer<const Executor &, Property>::value))
                            {
                                    return adapter<typename decay<
                                    typename prefer_result<const Executor&, Property>::type
                                    >::type>(0, asio::prefer(executor_, p));
                            }

                    template<typename Function>
                    typename enable_if<
                            execution::can_execute<const Executor &, Function>::value
                    >::type execute(ASIO_MOVE_ARG(Function) f) const {
                        execution::execute(executor_, ASIO_MOVE_CAST(Function)(f));
                    }

                    friend bool operator==(const adapter &a, const adapter &b)

                    ASIO_NOEXCEPT
                    {
                        return a.executor_ == b.executor_;
                    }

                    friend bool operator!=(const adapter &a, const adapter &b)

                    ASIO_NOEXCEPT
                    {
                        return a.executor_ != b.executor_;
                    }

                private:
                    Executor executor_;
                };

                template<int I = 0>
                struct allowed_t {
#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
                    template <typename T>
                    ASIO_STATIC_CONSTEXPR(bool,
                      is_applicable_property_v = (
                        is_executor<T>::value
                          || conditional<
                              is_executor<T>::value,
                              false_type,
                              is_sender<T>
                            >::type::value
                          || conditional<
                              is_executor<T>::value,
                              false_type,
                              is_scheduler<T>
                            >::type::value));
#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)

                    ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);

                    ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);

                    typedef blocking_adaptation_t<I> polymorphic_query_result_type;

                    ASIO_CONSTEXPR allowed_t() {
                    }

                    template<typename T>
                    struct query_member :
                            traits::query_member<
                                    typename blocking_adaptation_t<I>::template proxy<T>::type,
                                    allowed_t> {
                    };

                    template<typename T>
                    struct query_static_constexpr_member :
                            traits::query_static_constexpr_member<
                                    typename blocking_adaptation_t<I>::template static_proxy<T>::type,
                                    allowed_t> {
                    };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
                    template <typename T>
                    static ASIO_CONSTEXPR
                    typename query_static_constexpr_member<T>::result_type
                    static_query()
                      ASIO_NOEXCEPT_IF((
                        query_static_constexpr_member<T>::is_noexcept))
                    {
                      return query_static_constexpr_member<T>::value();
                    }

                    template <typename E, typename T = decltype(allowed_t::static_query<E>())>
                    static ASIO_CONSTEXPR const T static_query_v
                      = allowed_t::static_query<E>();
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
                    //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

                    static ASIO_CONSTEXPR blocking_adaptation_t<I>

                    value() {
                        return allowed_t();
                    }

                    friend ASIO_CONSTEXPR bool operator==(
                            const allowed_t &, const allowed_t &) {
                        return true;
                    }

                    friend ASIO_CONSTEXPR bool operator!=(
                            const allowed_t &, const allowed_t &) {
                        return false;
                    }

                    template<typename Executor>
                    friend adapter<Executor> require(
                            const Executor &e, const allowed_t &,
                            typename enable_if<
                                    is_executor<Executor>::value
                            >::type * = 0) {
                        return adapter<Executor>(0, e);
                    }
                };

#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
                template <int I> template <typename E, typename T>
                const T allowed_t<I>::static_query_v;
#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
                //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

                template<typename Function>
                class blocking_execute_state {
                public:
                    template<typename F>
                    blocking_execute_state (ASIO_MOVE_ARG(F)

                    f)
                    :

                    func_(ASIO_MOVE_CAST(F)(f)),
                            is_complete_(

                    false)
                    {
                    }

                    template<typename Executor>
                    void execute_and_wait(ASIO_MOVE_ARG(Executor) ex) {
                        handler h = {this};
                        execution::execute(ASIO_MOVE_CAST(Executor)(ex), h);
                        asio::detail::mutex::scoped_lock lock(mutex_);
                        while (!is_complete_)
                            event_.wait(lock);
                    }

                    struct cleanup {
                        ~cleanup() {
                            asio::detail::mutex::scoped_lock lock(state_->mutex_);
                            state_->is_complete_ = true;
                            state_->event_.unlock_and_signal_one_for_destruction(lock);
                        }

                        blocking_execute_state *state_;
                    };

                    struct handler {
                        void operator()() {
                            cleanup c = {state_};
                            state_->func_();
                        }

                        blocking_execute_state *state_;
                    };

                    Function func_;
                    asio::detail::mutex mutex_;
                    asio::detail::event event_;
                    bool is_complete_;
                };

                template<typename Executor, typename Function>
                void blocking_execute(
                        ASIO_MOVE_ARG(Executor) ex,
                        ASIO_MOVE_ARG(Function) func) {
                    typedef typename decay<Function>::type func_t;
                    blocking_execute_state<func_t> state(ASIO_MOVE_CAST(Function)(func));
                    state.execute_and_wait(ex);
                }

            } // namespace blocking_adaptation
        } // namespace detail

        typedef detail::blocking_adaptation_t<> blocking_adaptation_t;

#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
        constexpr blocking_adaptation_t blocking_adaptation;
#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
        namespace {
            static const blocking_adaptation_t &
                    blocking_adaptation = blocking_adaptation_t::instance;
        }
#endif

    } // namespace execution

#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)

    template<typename T>
    struct is_applicable_property<T, execution::blocking_adaptation_t>
            : integral_constant<bool,
                    execution::is_executor<T>::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_sender<T>
                    >::type::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_scheduler<T>
                    >::type::value> {
    };

    template<typename T>
    struct is_applicable_property<T, execution::blocking_adaptation_t::disallowed_t>
            : integral_constant<bool,
                    execution::is_executor<T>::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_sender<T>
                    >::type::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_scheduler<T>
                    >::type::value> {
    };

    template<typename T>
    struct is_applicable_property<T, execution::blocking_adaptation_t::allowed_t>
            : integral_constant<bool,
                    execution::is_executor<T>::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_sender<T>
                    >::type::value
                    || conditional<
                            execution::is_executor<T>::value,
                            false_type,
                            execution::is_scheduler<T>
                    >::type::value> {
    };

#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)

    namespace traits {

#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)

        template<typename T>
        struct query_free_default<T, execution::blocking_adaptation_t,
                typename enable_if<
                        can_query<T, execution::blocking_adaptation_t::disallowed_t>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = (is_nothrow_query<T,
                    execution::blocking_adaptation_t::disallowed_t>::value));

            typedef execution::blocking_adaptation_t result_type;
        };

        template<typename T>
        struct query_free_default<T, execution::blocking_adaptation_t,
                typename enable_if<
                        !can_query<T, execution::blocking_adaptation_t::disallowed_t>::value
                        && can_query<T, execution::blocking_adaptation_t::allowed_t>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
            (is_nothrow_query<T, execution::blocking_adaptation_t::allowed_t>::value));

            typedef execution::blocking_adaptation_t result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
 || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t,
                typename enable_if<
                        execution::detail::blocking_adaptation_t<0>::
                        query_static_constexpr_member<T>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef typename execution::detail::blocking_adaptation_t<0>::
            query_static_constexpr_member<T>::result_type result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return execution::detail::blocking_adaptation_t<0>::
                query_static_constexpr_member<T>::value();
            }
        };

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t,
                typename enable_if<
                        !execution::detail::blocking_adaptation_t<0>::
                        query_static_constexpr_member<T>::is_valid
                        && !execution::detail::blocking_adaptation_t<0>::
                        query_member<T>::is_valid
                        && traits::static_query<T,
                                execution::blocking_adaptation_t::disallowed_t>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef typename traits::static_query<T,
                    execution::blocking_adaptation_t::disallowed_t>::result_type result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return traits::static_query<T,
                        execution::blocking_adaptation_t::disallowed_t>::value();
            }
        };

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t,
                typename enable_if<
                        !execution::detail::blocking_adaptation_t<0>::
                        query_static_constexpr_member<T>::is_valid
                        && !execution::detail::blocking_adaptation_t<0>::
                        query_member<T>::is_valid
                        && !traits::static_query<T,
                                execution::blocking_adaptation_t::disallowed_t>::is_valid
                        && traits::static_query<T,
                                execution::blocking_adaptation_t::allowed_t>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef typename traits::static_query<T,
                    execution::blocking_adaptation_t::allowed_t>::result_type result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return traits::static_query<T,
                        execution::blocking_adaptation_t::allowed_t>::value();
            }
        };

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t::disallowed_t,
                typename enable_if<
                        execution::detail::blocking_adaptation::disallowed_t<0>::
                        query_static_constexpr_member<T>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef typename execution::detail::blocking_adaptation::disallowed_t<0>::
            query_static_constexpr_member<T>::result_type result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return execution::detail::blocking_adaptation::disallowed_t<0>::
                query_static_constexpr_member<T>::value();
            }
        };

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t::disallowed_t,
                typename enable_if<
                        !execution::detail::blocking_adaptation::disallowed_t<0>::
                        query_static_constexpr_member<T>::is_valid
                        && !execution::detail::blocking_adaptation::disallowed_t<0>::
                        query_member<T>::is_valid
                        && !traits::query_free<T,
                                execution::blocking_adaptation_t::disallowed_t>::is_valid
                        && !can_query<T, execution::blocking_adaptation_t::allowed_t>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef execution::blocking_adaptation_t::disallowed_t result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return result_type();
            }
        };

        template<typename T>
        struct static_query<T, execution::blocking_adaptation_t::allowed_t,
                typename enable_if<
                        execution::detail::blocking_adaptation::allowed_t<0>::
                        query_static_constexpr_member<T>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef typename execution::detail::blocking_adaptation::allowed_t<0>::
            query_static_constexpr_member<T>::result_type result_type;

            static ASIO_CONSTEXPR result_type

            value() {
                return execution::detail::blocking_adaptation::allowed_t<0>::
                query_static_constexpr_member<T>::value();
            }
        };

#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
        //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)

#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)

        template<typename T>
        struct static_require<T, execution::blocking_adaptation_t::disallowed_t,
                typename enable_if<
                        static_query<T, execution::blocking_adaptation_t::disallowed_t>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid =
            (is_same<typename static_query<T,
                    execution::blocking_adaptation_t::disallowed_t>::result_type,
                    execution::blocking_adaptation_t::disallowed_t>::value));
        };

        template<typename T>
        struct static_require<T, execution::blocking_adaptation_t::allowed_t,
                typename enable_if<
                        static_query<T, execution::blocking_adaptation_t::allowed_t>::is_valid
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid =
            (is_same<typename static_query<T,
                    execution::blocking_adaptation_t::allowed_t>::result_type,
                    execution::blocking_adaptation_t::allowed_t>::value));
        };

#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)

        template<typename T>
        struct require_free_default<T, execution::blocking_adaptation_t::allowed_t,
                typename enable_if<
                        is_same<T, typename decay<T>::type>::value
                        && execution::is_executor<T>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);

            typedef execution::detail::blocking_adaptation::adapter<T> result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

        template<typename Executor>
        struct equality_comparable<
                execution::detail::blocking_adaptation::adapter<Executor> > {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
        };

#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

        template<typename Executor, typename Function>
        struct execute_member<
                execution::detail::blocking_adaptation::adapter<Executor>, Function> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);

            typedef void result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

        template<typename Executor, int I>
        struct query_static_constexpr_member<
                execution::detail::blocking_adaptation::adapter<Executor>,
                execution::detail::blocking_adaptation_t<I> > {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef execution::blocking_adaptation_t::allowed_t result_type;

            static ASIO_CONSTEXPR result_type

            value()

            ASIO_NOEXCEPT
            {
                return result_type();
            }
        };

        template<typename Executor, int I>
        struct query_static_constexpr_member<
                execution::detail::blocking_adaptation::adapter<Executor>,
                execution::detail::blocking_adaptation::allowed_t<I> > {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef execution::blocking_adaptation_t::allowed_t result_type;

            static ASIO_CONSTEXPR result_type

            value()

            ASIO_NOEXCEPT
            {
                return result_type();
            }
        };

        template<typename Executor, int I>
        struct query_static_constexpr_member<
                execution::detail::blocking_adaptation::adapter<Executor>,
                execution::detail::blocking_adaptation::disallowed_t<I> > {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef execution::blocking_adaptation_t::allowed_t result_type;

            static ASIO_CONSTEXPR result_type

            value()

            ASIO_NOEXCEPT
            {
                return result_type();
            }
        };

#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

        template<typename Executor, typename Property>
        struct query_member<
                execution::detail::blocking_adaptation::adapter<Executor>, Property,
                typename enable_if<
                        can_query<const Executor &, Property>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
            (is_nothrow_query<Executor, Property>::value));

            typedef typename query_result<Executor, Property>::type result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

        template<typename Executor, int I>
        struct require_member<
                execution::detail::blocking_adaptation::adapter<Executor>,
                execution::detail::blocking_adaptation::disallowed_t<I> > {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);

            typedef Executor result_type;
        };

        template<typename Executor, typename Property>
        struct require_member<
                execution::detail::blocking_adaptation::adapter<Executor>, Property,
                typename enable_if<
                        can_require<const Executor &, Property>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
            (is_nothrow_require<Executor, Property>::value));

            typedef execution::detail::blocking_adaptation::adapter<typename decay<
                    typename require_result<Executor, Property>::type
            >::type> result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)

        template<typename Executor, typename Property>
        struct prefer_member<
                execution::detail::blocking_adaptation::adapter<Executor>, Property,
                typename enable_if<
                        can_prefer<const Executor &, Property>::value
                >::type> {
            ASIO_STATIC_CONSTEXPR(bool, is_valid = true);

            ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
            (is_nothrow_prefer<Executor, Property>::value));

            typedef execution::detail::blocking_adaptation::adapter<typename decay<
                    typename prefer_result<Executor, Property>::type
            >::type> result_type;
        };

#endif // !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)

    } // namespace traits

#endif // defined(GENERATING_DOCUMENTATION)

} // namespace asio

#include "asio/detail/pop_options.hpp"

#endif // ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP
